In recent years, the size of computers has tended to decrease despite the fact that the computing capabilities of computers has tended to increase. The size reduction may be attributable in part to the continuing push to develop smaller packaging for computer components. One exception to this trend toward smaller packaging of computer components is in the area of power supplies. While the size of computer components has generally decreased, power supplies have not.
Most computers sold commercially implement power factor corrected switching power supplies and/or power factor correction circuits. Power factor is a measure of the cosine of the angle between the alternating current voltage signal and supplied alternating current signal. Power supplies and circuits that implement power factor correction attempt to bring the power factor as close to unity as possible regardless of the power delivered by or through them.
The size of power factor corrected switching power supplies has remained relatively constant due mostly to the size of the common-mode inductors (acting as electromagnetic interference filters), as well as the size of boost inductors. The common-mode and boost inductors may have a primary winding and a secondary winding, coupled by magnetic material through which the magnetic flux flows. Because of this construction, common-mode and boost inductors may be bulky and thus limit the ability to achieve size reductions.
The present invention may address one or more of the above issues.